ABSTRACT About 1.1 million people are living with HIV (PLWH) in the US, with an estimated 39,782 individuals newly diagnosed with HIV in 2016. The Multicenter AIDS Cohort Study (MACS) and the Women?s Interagency HIV Study (WIHS) are two of the longest standing HIV cohort studies in the United States. Established in 1984 and 1993, respectively, these US-based cohorts currently follow 2,235 men and 2,304 women living with HIV, alongside high-risk but uninfected controls. HIV is at epidemic proportions in the nation?s capital, with overall HIV prevalence of 1.9% among the District of Columbia (DC) adult and adolescent residents. Approximately 3.7% of DC residents aged 40 to 49 years and 5.2% of residents aged 50 to 59 years are living with HIV. The highest life time risk of acquiring HIV in the U.S. is highest in DC with an estimated 1 in 17 individuals anticipated to acquire HIV in their lifetime, followed by 1 in 56 risk among the neighboring Maryland residents. Continuing to follow the women we have recruited and expanding our cohort to include a representative group of men and women is imperative in this region with epidemic levels of HIV. Our research will be focused on understanding the behavioral and social determinants that contribute to long term treatment success and failure, with a focus on identifying key resilience factors that may translate into innovative interventions to achieve the global goals of the HIV care continuum, to improve treatment uptake and viral suppression to decrease morbidity and mortality. We have four aims to achieve our goals. (1) To continue our strong collaborative relationship with the national MACS/WIHS CCS in protocol development, implementation, participant enrollment, retention, data acquisition, and sub-study participation; (2) To lead the CCS-wide effort to understand the psychosocial and behavioral determinants that contributes to treatment adherence, virologic suppression, and healthy coping among PLWH in the US; (3) To determine the effectiveness of treatment and prevention guidelines and identify disparities in service delivery for common morbidities with high associated mortality; and (4) To explore HIV, aging, and associated co-morbidities, including the role of microvascular/vascular function, the microbiome, neurocognitive decline in the context of contemporary antiretroviral treatment regimens, and hearing and balance disorders among men and women. Our long-term goal is to improve the health of people living with HIV and to help prevent those without HIV from seroconverting.